What will half a quart too much transmission fluid do?

SOURCE: truck wont shift automatic. stays in 3rd gear. can shift manually

either repair or replace the transmission...sounds like the sensor went out

SOURCE: transmission shifts hard down from highway gear only (D>3rd)

I had the same thing! It was a computer issue. It only cost me about $35.00.

SOURCE: transmission does not always shift into overdrive

Governor pressure sensor or solenoid is going bad. To replace them drop the tranny pan, remove the filter , and the parts are pretty ez to get to. These aren't cheep thou, but replace them as a set. Parts will probly run about $200.

SOURCE: Transmission Not Going into Overdrive

First check and make sure the fluid is full. The most likely cause is a failed solenoid pack. Circuit codes normally mean something electrical not mechanical has failed. The solenoid pack is on the outside of trans pretty easy to replace.

SOURCE: 1997 dodge ram 1500 (360) transmission.

My 95 Cummins Dodge had the same problem and adding "Lucas Transmissiion Fix" cured it completely and permanently.

Thier claim is as follows:


Lucas Transmission Fix is a non-solvent formulas that stops slip, hesitation and rough shifting in worn transmissions and completely eliminates most seal leaks. Use in any transmission for preventative maintenance.Use also in light duty manual transmissions to increase shifting ease and transmission life.
Key Benefits

• Contains no solvents
• Lowers operating temperatures and stops foaming
• Can be added to existing fluid without draining any out
• Effective in an extremely high percentage of cases